1. Field of the Invention
The invention relates to a piezoelectric transformer driving device operable to drive a piezoelectric transformer, a cold-cathode tube inverter and a cold-cathode tube driving device that are operable to drive a cold-cathode tube using the piezoelectric transformer driving device, and an electrophotographic image forming apparatus using the piezoelectric transformer driving device, the cold-cathode tube inverter, or the cold-cathode tube driving device.
2. Description of Related Art
A conventional power supply device used for an electrophotographic image forming apparatus has been known, in which an output signal of a piezoelectric transformer driving device, which comprises a voltage-controlled oscillator (hereinafter “VCO”), controls a piezoelectric transformer, which can transform a low voltage input to a high voltage output using a resonant oscillation of a voltage oscillator, so as to output a high voltage (for example, Japanese Patent Application Laid-Open No. 2006-91757).